MAKING GOOD OLIVE OIL

Growing up I understood that olive oil was important. Maybe I didn’t know that olive oil had a 5,000 year old history and had been used in rituals, for skin care, as a medicine and to light lamps, but I knew we used it when we cooked. And I knew how surprised the family was when we found out our neighbors used different oil than we did, an open betrayal of the region of Italy their ancestors came from. There is no doubting that olive oil inspires dedication, fascination and opinion amongst its users. Below is some information on the olive oil making process and what goes into a good olive oil. Notice that at any step in the oil making process, the techniques range from traditional, hand-only labor to the use of  high-speed, efficient machines. This holds true for growing, harvesting processing and grading.

Growing

Okay, square one - to make olive oil you first need ripe olives which come from olive trees. For that you need a climate well suited to the variety of olives you are growing. This includes such locations as Portugal, Spain, Italy, Turkey and Greece. There are areas, like Northern California, whose weather patterns mimic these Mediterranean climates and thus produce excellent olives. There are numerous olive varieties, hundreds in Italy alone, so finding a variety to produce the oil you desire in a reasonable climate is not too hard. Olive trees grow 20 to 40 feet tall, so the hard work is caring and maintaining the trees. Some varieties are trellised, which can require more pruning and cultivation than trees. Olive trees must be adequately maintained to ensure blossoming in the spring and good production for the fall harvest.

Harvesting

To produce flavorful oil you must know when your olives have the greatest amount of the best oil. Each variety of olive ripens to its own shade of yellow-green, green, brown or reddish brown, making it very tricky to know when harvest is ideal. Harvest too early and the young, green olives may turn the oil bitter and produce low quantities of oil. If you harvest too late the olives may have a chance to spoil or ferment, yielding oil of poor flavor and a dark color. Choosing the perfect harvest time takes years of experience, but modern chemical analysis is often used to aid the timing.

Olives can be harvested by hand, employing the use of ladders, rakes and baskets. Some olives are simply allowed to fall to ground when ripe and then gathered, however unpredictable timing of this harvest may lead to quantity and quality issues. The physically demanding job of hand-selecting olives at harvest yields the most desired olives and does minimal damage to the tree. You need experienced pickers who can get only the ripe olives and work efficiently. Olives can also be beaten or shaken from the tree, either manually or using a mechanical shaker. Large nets are spread under the tree to facilitate gathering. This method yields olives with a wide range in quality and can damage some olives or the tree itself. Rising global wages have encouraged the improvement of mechanical methods. In Northern California, where plantings are on the rise, many new olive trees are trellised similar to grapes to allow for mechanical harvesting.  Regardless of the harvest method chosen, processing should begin as soon as possible to protect against oxidation or fermentation occurring during any period of storage.

Processing - Crushing & Pressing
After harvest olives are washed and any leaves or sticks are removed. Next the olives are crushed. Again, techniques vary with the size and sophistication of the facility. Crushing may be done with devices ranging from donkey-powered, stone grinding wheels to high-speed, rotating, stainless steel drums. When crushing, also called the “first press”, is complete the olives have been reduced to a thick paste consisting primarily of olive oil, olive flesh and olive pit pieces. During crushing some oil is produced. It is this “first press” oil that has the highest quality and purity, but more delicious oil can be extracted from the paste. This can be done by spreading the paste on special disks, placing them in a stack and then squeezing them with a press. Some presses use hand cranks or screws while others use hydraulic power. Extracting oil could also be done by spinning the paste at high speeds in a drum that allows the paste to separate. Filtration can be used during or after these steps to help separate oil from paste.  The oil, divided in its various grades, is now ready for bottling.

Grading - Flavor, Texture and Aroma

Oil is the oilve’s great secret. A raw olive is not a taste treat, but the oil it renders can be a satisfying combination of many flavors and scents. One can try with words to describe these characteristics, but you need to taste oil to give these words meaning. Don’t get lost in the vocabulary lesson - the primary flavor of olive oil should be the pungent, pleasingly bitter taste of the olive fruit. Olive oil will exhibit a wide range of flavors, textures an aromas depending on variety, area grown, processing style, etc.,. Each variety expresses it characters differently. Desirable flavors in oil are described as earthy, peppery, grassy, spicy, herbaceous, nutty and fruity. Flavors in oil that detect it has gone bad (or maybe wasn’t so good in the first place) are described as metallic, cucumbery, smoky, cheesy, moldy, meaty, salty or burnt. Aroma is a much more subtle characteristic of an olive oil. Good aromas are described as floral, flowery, earthy or sweet. Bad aromas are moldy, cheesy and smoky. The texture of olive oil runs from rich & full-bodied to smooth & buttery to light & delicate. Color varies from light yellow to golden to green. To me, it is the flavors, colors and aroma of a particlar oil that make it acceptable, but no olive oil primer would be complete without discussing grades of oil.

This grading system is not without some controversy. In fact, although most of the world’s olive oil comes from participating countries, the United States is not a member of the IOOC and the US Department of Agriculture does not legally recognize IOOC classifications (such as extra-virgin olive oil). The USDA uses its own grades (Fancy, Choice, Standard and Substandard), however the California Olive Oil Council, a trade group supporting California’s growing olive oil production, wants the US to adopt international standards. Unfortunately this leaves some less reputable oil producers to play games with blending and label wording. For example, foreign producers can add other oils, like less expensive canola oil, to their olive oil and still market it in the United States as “extra virgin olive oil” because that term does not have a legal defintion here. It is also generally accepted that all of the olive oil labeled “bottled in Italy” or “produced in Italy” does not come from olives that were grown or even processed in Italy.

Bottling and Storage
Bottling should not be overlooked as it affects the storage and use of the olive oil. Olive oil is stored in all types of containers, from wooden barrels to tin cans to the familiar glass bottle. If oil is stored by a processor or by a home consumer, the oil’s enemies in storage are the same – sunlight, heat and air. Avoid exposure to sunlight. Aside from the potential for breaking down the oil from the heat, sunlight will adversely affect the color of your oil, darkening it over time. For most olive oils the optimum storage temperature is 65°F to 70°F. During storage, temperatures about 77°F can reduce the nutritional value of olive oil by breaking down vitamin E. Olive oil can be refrigerated or frozen with little problem. At temperatures below 59°F olive oil may crystallize, however returning to the oil to a temperature around 65°F will make the oil clear again without quality loss. It is important for your oil to be stored in a way to minimize air exposure. Limiting the surface area of your stored oil will reduce air exposure. This is why it is a good idea to transfer your oil to a smaller container when your bottle is half empty. It is also important to ensure that the lid of your container is tight. Oil reacting with oxygen will eventually become rancid. Likewise, a tight seal with keep unwanted odors from your olive oil and keep out moisture.

The End?
Hopefully the preceding info will be of some use the next time you buy or use olive oil. Better yet, it had left you with questions like, “Why does everyone say olive oil is so healthy?”, “Are the awards given for great oil?” or “What fruity flavors do you really taste in good oil?” If you would like more information I recommend visiting the California Olive Oil Council website, located at www.cooc.com. Buon’ Appetito!

“Good oil, like good wine, is a gift from the gods. The grape and the olive are among the priceless benefactions of the soil, and were destined, each in its way, to promote the welfare of man.”
                                -George Ellwanger, Pleasures of the Table (1902)

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